Listar Revista de Ciencia y Tecnología por título
Mostrando ítems 33-52 de 79
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Harnessing titanium dioxide surface toward novel functional materials
(2015)The ever-increasing worldwide energy consumption has led the society to quest for novel and functional materials that can be used in the development of solar fuels to some extent lessen the dependence on fossil fuels. In ... -
Historia del campo geomagnético de Costa Rica
(2011-02-15)The study of the geomagnetic field began with the publication of the book De Magnete (1600) of Sir William Gilbert (1504-1603). By influence of Sir Edmund Halley the British Marine is obligated to make measurements of the ... -
Identificación de modelos de orden reducido a partir de la curvatura de reacción del proceso
(2009-01-13)A general identification procedure is given, for first and second orders plus time delay models, that uses two or three arbitrary points over the process reaction curve. Two simplified versions of the methods are described: ... -
IMPACTO DEL CRECIMIENTO ECONÓMICO INDUSTRIAL SOBRE LOS RECURSOS ENERGÉTICO E HÍDRICO EN COSTA RICA
(2012-11-26)An empirical relationship between water consumption, energy consumption and industrial GDP was established, for the case of Costa Rica. This relationship may be useful in ... -
Importancia de la batimetría de las planicies basales en la propagación de tsunamis transoceánicos
(2009-04-29)The initial form of a tsunami originated by an homogeneous seismic source consists on a simple wave front. While the tsunami propagates in deep water, this simple form suffers several modifications by the tsunami's interaction ... -
Kinetics of the fischer esterification of palm fatty acids with isopropanol and butyl-cellosolve
(2009-01-13)Fischer esterification of the mixture of palm fatty acids can be achieved in 80% conversion, under conditions of reactive distillation and methanesulphonic acid as catalyst. The volatility of the H2O/alcohol azeotrope ... -
La cinética de la esterificación de ácidos carboxílocos es de segundo orden con repecto al alcohol
(2009-01-13)Esterification of carboxylic acids with alcohols is considered as AAC2 type reaction. The specific rate of esterification of acetic acid with methanol, in mixtures of acetonitrile-methanol showed a quadratic dependence on ... -
La lógica difusa en ingeniería: principios, aplicaciones y futuro
(2009-01-13)Fuzzy logic is a mathematical tool that mimics the way humans manage and process information. It is a method of great simplicity for processing of information, decision making and process control. This article discusses ... -
La naturaleza del enlace químico 2013 ¡No existe tal cosa llamada orbital!
(2013-06-28)Despite the fact that the chemical bond is a fiction, although convenient and nearly harmless, it plays an enormous role in the thinking, and especially the education, of chemists at all levels. Much further fiction has ... -
La tierra moler o "diatomita" como sistema de remoción de sustancias químicas en el laboratorio.
(2009-04-29)Experiments were carried out, to determine the capability of diatomite for the disposal of laboratory residues. Experimentation with different organic solvents (ethyl ether, acetone, ethyl acetate, hexane and ethanol) ... -
Las cuerdas magnéticas
(2009-01-13)The conception of the magnetic string is presented; it is an infinitely thin bundle of magnetic flux lines. They are surrounded by a film of current that rotates around them, and are a solution of Maxwell’s equations. Their ... -
Levantamiento topográfico de una aldea precolombina (900-1550 a.C.)
(2018)The authors discuss methodological aspects of the topographic and archaeological analyses being carried out in Barranca, a pre-Columbian settlement in San Ramón, Alajuela. A discussion is also presented on the relevance ... -
Lignanos de Zanthoxylum acuminatum
(2009-01-13)From the aerial parts of Zanthoxylum acuminatum (Rutaceae) collected in Upala, Alajuela, Costa Rica were isolated the known lignans hinokinin, (+)-asarinin, (+)- piperitol, (+)-kobusin, and epi-kobusin. In addition to the ... -
Long-term voltage stability assessment using Quasi-Steady State Simulation in Matlab
(2015-06-17)A Quasi Steady State Simulator (QSSS) for long term voltage stability assessment has been developed, tested and verified in Matlab. Theory and modelling assumptions behind QSSS are explained, including many elements present ... -
Manejo responsable de los desechos radiactivos en la Universidad de Costa Rica
(2009-01-13)The Radiation Safety Program (RSP) of the University of Costa Rica established in 1990, handles the radioactive waste generated at the University. A centralized storage waste room is used by the Atomic, Nuclear and Molecular ... -
Microrredes en la red eléctrica del futuro - caso Huatacondo
(2014-07-07)This paper proposes a new paradigm related to electrical power systems, known as Microgrids, with emphasis on those systems that must operate in isolated communities. It redefines the concept of supervisory control and ... -
Modelación de la emisión de compuestos orgánicos volátiles en sistemas de aereación mediante un modelo de dos zonas simplificado
(2009-01-13)A new simplified mass-transfer model was developed to describe the volatile organic compounds (VOC) emission rates from diffused aeration systems. The model takes into consideration that the VOC mass transfer occurs in two ... -
Modelación de la transferencia de oxágeno en sistemas de aereación mediante un modelo de dos zonas simplificado
(2009-01-13)A new two zone simplified oxygen mass-transfer model with an analytical solution was proposed and used to analyze the unsteady state reaeration data of diffused reaeration systems in order to find the volumetric mass-transfer ... -
Modelización directa y comparación de los principales dispositivos geoeléctricos
(2009-04-29)With the purpose of comparing the main geolectrics arrays used for the realization of vertical electrical sounding, a direct simulation is presented, considering two geologic models. The investigation depth, precision in ... -
Monitoreo ambiental con detectores termoluminiscentes en Costa Rica
(2009-01-13)Using thermoluminiscent dosimeters (Harshaw TLD-200) the first set of Costa Rica data on absorbed doses in air from natural radiation is obtained. During the period September 1996 through October 2000 eight different sites ...